Pianoforte action



F. KOTH. PIANoPoRTB AGTIGN.

UNITED STATES PATENT OFFICE.

FREDERlGK VOTE. OF NEW YORK, N. Y.

PIANO-FORTE ACTION,

Speeilication forming part of Letters Patent No. 48,565, dated July 4,1865.

To all whom it may concern.-

Beitknown thatl, FaEDEEicK Kofrmofhew York, in the county and State ot' New York, haveinv'ented a new and improved Rane-Forte Action; and l do hereby1 declare that the following is a full and exact description thereof, reference being had to the accompanying drawings, and to thelettcrs or" reference marked thereon.

Thenature of. my invention consists in the arrangement of a second jack on the key-lever acting upon the hammer-butt insuch a inanner as to hold the hammer near the string to allow the usual jack to pass readily by the least motion of the key under the hammer-butt, so as to operate said hammer in such a manner as to produce a repetition ot' blows by a very slight rise of the endet the key.

In the accompanying drawings, Arepresents the keyllever, to which the usual jack, B, and back check, C, are attached and arranged in the usual manner.

E is the ange, to which the hammer-butt D of the hammer F is pivoted.

G is a second inch hinged on the end of a lever, E, the other end of which lever is hinged on the projection J fast to the key-lever A.

sis a spring situated belov7 the lever H to hold the same, as eell as this second jack G, up.

n is a stop fast to the key A, the upper end of which projects over the top of the lever H to prevent the action of the spring s forcing A said lever E, and consequently the jack G, too

far upward.

Lis a stop capableiof being regulated and acting upon a projection, w, on the end ot' the jack B, whereby said jack is moved away from c under the hammer-butt D.

N is a stop capable of being regulated and acting against the top side of the lever H, to regulate and tix the upwardV motion of said lever H, and consequently of the jack G.

M represents one of the strings.

The operation is as follows: By the motion of the keyA the jack B as Well. as the jacl; G

\ ont of said recess. The jachB acts, therefore, on the hammer-butt so as to cause the harnmer F to strike the string M in the usnal inanner when the projection w on the levier end of said jack B cornes in contact with the stop L, so as to move the upper end oi' said jack away from the under side of the hammer-butt D when the hammer falls again, and is caught in its fall by the back check, G, and the jack G forcing the latter alittle downward. Theleastmotion of the lrey A will canse the back check, C, to liberate the hammer, when the action ot' the spring s will force the jack G upward until stopped bythe stopN, and moving thereby the hammer F upward till within a short distance ci' the string, and in such a posit-ion that the bottom of the hammer-butt D will be in a line with the tcp of the jack B, when, by a slight motion of the end ot the key A., the projection w of thejaclr B will be brought'clear of its stop L and said vjack B will he moved under the bottom ot' the hammer-butt D, ready to force the hammer-'F upward thatv short distance to strike the string, and permit thereby a quick repetition of blows with only a very slight motion ot' the end of the hey.

Figure l represents an enlarged view of the flange to which the hammer-butt is pivoted. The screw which tightens the lower part to the upper has a small groove, o, turned on in its upperpart, into which a .stationary pin, is tted in such a manner as to allow the screw to turn freely, but at the 'same time prevent the same from moving. The thread is in that case only cnt on the lower part of the screw, and by which arrangement the pivot-pin of the hammer-butt can be regulated with greater nicety and accuracy.

The hammer is made by the use of cork P, cut or shaped in the required in anner and then covered with very soft leather or cloth d. rEhe baci; check, C,has'likewise a thickness of cork, a, on its face covered with soft leather or cloth f, and in the same manner is the bottom of the hammer-butti? made, wherep represen ts a piece of corh'covered with leather or cloth t.

' are movedupward,an`d acttogetheron thehani- The substitution of cork in piano-actions in mecbuttl). The jack G is stopped by its stop places where felt has always been used at pres- N when the hammer has arrived at a certain ent presents many advantages independent of height a short distance fromthe string M, but its very great saving in the expense. When as said jack Gr works in a deep recess or 'notch l felt is bent around the end ofthe hammer-stem in the hammerbutt the saine can never come the inner side is naturally very much conipressed, and byvwhieh it losesa great deal of elasticity, while orli, being cut out of a solid pieee,retains its elasticity throughout its whole thickness. ln places where felt is only aplie'd in thin layers, as at the bottom ofthe ham mer-butt, or on the face of the back check, its elasticity is very often completely'destroyed by the application of too much glue, with which' the felt is attached tothe Wood, and in which case the porous nature of the felt allows the glue to penetrate and absorbs the same, so as *o become quite hard,instead of beiug'sft and elastic, while from the nature of cork the glue can never'penetrate the same, and can conse! quetly not destroy its quality.

Instead of making the endofthe hammer altogether of cork, a small piece of felt may in FREDERICK KOTH. Witnesses:

HENRY E. Roaman, E. W. BoGARnUs. 

